Video cassette recorders usually are so arranged that a magnetic tape is held within a cartridge or cassette and being passed in front of transducing heads, also known as magnetic transducer heads, for scanning of magnetic data encoded or recorded on the magnetic tape. In one type of system, which is widely used, spiral scanning is employed, in which the magnetic tape is passed in a spiral path over a usually cylindircal scanning arrangement. The tape passes thereover in the form of a helix and is scanned by magnetic heads which rotate at high speed in a ring-shaped slot of the scanning head. The tape moves with slow speed in a linear direction--that is, linearly with respect to the tape--as it is being scanned at high speed by the rapidly rotating heads. Such video magnetic tape apparatus is frequently used with tape retained in magnetic tape cassettes, in short, in cassettes or cartridges. Structures are provided for pulling the tape out of the cassette after it has been introduced into the housing of a scanning apparatus. The tape, as it is being pulled out of the cassette, is then placed by suitable guide elements into a scanning path, in which it is contacted by further drive and guide apparatus. Magnetic tape is sensitive with respect to tension and must not be overstressed; on the other hand, the tape should fit snugly about the guide elements and other structures in the tape path, that is, should not have any free or drooping loops or the like, or loose or slack zones, since, then, the correct position of the magnetic tape in its path is not always ensured when the tape is operating, that is, is being scanned.
U.S. Pat. No. 4,636,887, Kato et al., (claiming priority of a Japanese application 19 22 59 - 82, filed Nov. 1, 1982) describes a tape loading arrangement for a recording/reproducing apparatus in which the tape withdrawal process is subdivided into a plurality of partial withdrawal steps. The first two such steps are carried out without controlling tape tension at all. It has been found that, during the uncontrolled pull-out of tape, no definite or controlled longitudinal tension can be applied on the tape and, therefore, sagging or loose loops of tape may form. Transition from uncontrolled pull-out to controlled pull-out steps at later partial operating steps require careful control to prevent impacts or sudden jars. To prevent such jarring, a comparatively, complex arrangement utilizing a plurality of sensors is suggested which, in dependence on the instantaneous position of the tape, control drive motors for the loading apparatus and for the tape reel disks or tables. They also control mechanical brakes, sequentially, to thereby control the final operating position and condition of the tape. A microprocessor is used to control the respective steps.
U.S. Pat. No. 3,673,348 describes a tape recorder apparatus with a tape loading arrangement in which a tape length compensating lever is used, acting and operative at the initiation of the band pull-out step. The apparatus uses a tensioning lever which is part of the structure of the cassette which, however, does not have any tape control function. Thus, no arrangements are provided in which the tape loading, or return process can be influenced to also control the length and tension of tape being pulled out from a cassette when the lever reaches one or the other of its terminal positions in its operating movement.